title: Glycyrrhizinate reduces portal hypertension in isolated perfused rat livers with chronic hepatitis.
abstract: OBJECTIVE
  To investigate the effects of diammonium glycyrrhizinate (Gly) on portal hypertension (PHT) in isolated portal perfused rat liver (IPPRL) with carbon tetrachloride (CCl₄)-induced chronic hepatitis.
  
  
  METHODS
  PHT model was replicated with CCl₄ in rats for 84 d. Model was identified by measuring the ascetic amounts, hepatic function, portal pressure in vivo, splenic index, and pathological alterations. Inducible nitric oxide synthase (iNOS) in liver was assessed by immunohistochemistry. IPPRLs were performed at d₀, d₂₈, d₅₆, and d₈₄. After phenylephrine-induced constriction, Gly was geometrically used to reduce PHT. Gly action was expressed as median effective concentration (EC₅₀) and area under the curve (AUC). Underlying mechanism was exploited by linear correlation between AUC values of Gly and existed iNOS in portal triads.
  
  
  RESULTS
  PHT model was confirmed with ascites, splenomegaly, serum biomarkers of hepatic injury, and elevated portal pressure. Pathological findings had shown normal hepatic structure at d₀, degenerations at d₂₈, fibrosis at d₅₆, cirrhosis at d₈₄ in PHT rats. Pseudo lobule ratios decreased and collagen ratios increased progressively along with PHT development. Gly does dose-dependently reduce PHT in IPPRLs with CCl₄-induced chronic hepatitis. Gly potencies were increased gradually along with PHT development, characterized with its EC₅₀ at 2.80 × 10⁻¹⁰, 3.03 × 10⁻¹¹, 3.77 × 10⁻¹¹ and 4.65×10⁻¹¹ mol/L at d₀, d₂₈, d₅₆ and d₈₄, respectively. Existed iNOS was located at hepatocyte at d₀, stellate cells at d₂₈, stellate cells and macrophages at d₅₆, and macrophages in portal triads at d₈₄. Macrophages infiltrated more into portal triads and expressed more iNOS along with PHT development. AUC values of Gly were positively correlated with existed iNOS levels in portal triads.
  
  
  CONCLUSIONS
  Gly reduces indirectly PHT in IPPRL with CCl₄-induced chronic hepatitis. The underlying mechanisms may relate to rescue NO bioavailability from macrophage-derived peroxynitrite in portal triads.
authors.affiliation: Xin Zhao, Bo Deng, Xue-Yan Xu, Shi-Jun Yang, Tao Zhang, Da-Yong Cai, Institute of Medicinal Plant Development, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing 100193, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Bo
authors.initials: B
authors.lastname: Deng
authors.forename: Xue-Yan
authors.initials: XY
authors.lastname: Xu
authors.forename: Shi-Jun
authors.initials: SJ
authors.lastname: Yang
authors.forename: Tao
authors.initials: T
authors.lastname: Zhang
authors.forename: Yi-Jun
authors.initials: YJ
authors.lastname: Song
authors.forename: Xiao-Ting
authors.initials: XT
authors.lastname: Liu
authors.forename: Yue-Qi
authors.initials: YQ
authors.lastname: Wang
authors.forename: Da-Yong
authors.initials: DY
authors.lastname: Cai
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D002251:Carbon Tetrachloride; D056487:Chemical and Drug Induced Liver Injury, Chronic / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D003094:Collagen / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D019695:Glycyrrhizic Acid / Q000494:pharmacology*; D006975:Hypertension, Portal / Q000188:drug therapy* / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D008099:Liver / Q000098:blood supply* / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008106:Liver Cirrhosis, Experimental / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism / Q000503:physiopathology; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism; D008297:Male; D052247:Nitric Oxide Synthase Type II / Q000378:metabolism; D010477:Perfusion; D030421:Peroxynitrous Acid / Q000378:metabolism; D017082:Portal Pressure / Q000187:drug effects*; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
chemical_list: D000959:Antihypertensive Agents; D030421:Peroxynitrous Acid; D019695:Glycyrrhizic Acid; D003094:Collagen; D002251:Carbon Tetrachloride; D052247:Nitric Oxide Synthase Type II; C496318:Nos2 protein, rat
keywords: Chronic hepatitis; Diammonium glycyrrhizinate; Inducible nitric oxide synthase; Isolated portal perfused rat liver; Portal hypertension